Rotary table assembly



June 18, 1940. 1 F. BAAsH ROTARY TABLE ASSEMBLY Filed Deo. 17, 1938 2SheetsSheet 2 3 w .w 3 9 3 3 Z Z 2 Z 2 .4M 9 6 6 Q 2 WUMW 3 vl fl' 2 wwww Patented June 1%. 1940 UNITED STATES PATENT OFFICE ROTARY TABLE ASSEMBLY Application December 17, 1938, Serial No. 246,424

10 Claims.

This invention relates to well drilling equipment and relates moreparticularly to the rotaries or rotary table units of well drillingrigs. A general, object ci this invention is to provide a prac- 5 tical,effective and improved master bushing and rotary table.

In the rotary method of well drilling a rotary table is provided in thederrick and is driven by engine or other power means to effect rotavtion of the drilling string. The rotary table is usually provided with alarge central opening equipped with what is known as a master bushing.The master bushing in turn is adapted to receive a drive bushing orKelly bushing for transmitting rotation to the drive 'stem of thedrilling string. During the drilling operations the rotary table and theassociated equipment are subjected to severe strains and very hardusage. This sometimes results in movement and slap between thecontacting surfaces of the table and the master bushing and the bushingoften works or wears loose in the table.

An obi-ect of this invention is to provide a master bushing that remainstight in the opening of the rotary tahle and does not workloose or movein the 'ta-hie, and therefore, does not cause wearing of the engagingtable and bushing surfaces.

Another object of this invention is to provide a master bushing andtable assembly in which.

the master bushing accurately ts the table'to assure a proper iit of theslips and drive bushings in the master bushing.

Another object of this invention is to provide a sectional masterbushing embodying novel means for holding the bushing sections ltight inthe opening of the rotary table and for holding the sections againstrelative movement and play. Another object of this invention is toprovide 40a master bushing of the character mentioned that automaticallytightens itself in the rotary table even though the opening of the tablemay be worn or irregular.

Another object of this invention is to provide a Minas-ter bushing ofthe character mentioned in which the means for holding the bushing tightin the rotary table automatically compensates for any wear that mayoccur and, therefore, maintains the firm engagement of the bushing inthe table throughout the period of use of the bushing. Another object ofthis invention is to provide a ina-ster bushing of the charactermentioned in which the means for holding the bushing tight in the rotarytable is automatically released or retracted when the bushing isinserted in and (Cl. Z55-23) removed from the table and does not in anyway interfere with the easy insertion and removal of the bushing.

A further object of this invention is to provide a master bushing of thecharacter mentioned that is simple and inexpensive to manufacture.

The various objects and features of my invention will be fullyunderstood from the following detailed description of typical preferredforms and applications oi the invention, throughout which descriptionreference is made to the accompanying drawings, in which:

Fig. l is a central vertical detailed sectional View of a typical rotarytable and a master bushing of the present invention arranged therein.Fig. 2 is a plan view of the bushing removed from the table. Fig. 3 is aside elevation of one of the bushing sections being a view taken asindicated by line 3-3 on Fig. 2. Fig. 4 is an enlarged vertical detailedsectionai view of the bushing section illustrated in Fig. 3 showing oneof the Wedge elements and its actuating means in the released orretracted condition. Fig. 5 is a horizontal detailed sectional viewtaken substantially as indicated by line 5-5 on Fig. fl. Fig. 6 is afragmentary horizontal detailed sectional view taken as indicated byline SDS on Fig. 4. Fig. 7 is a perspective view of a lifting tool thatmay be utilized to handle the bushing sections, and Fig. 8 is a Viewsimilar to Fig. 4 illustrating another form of the invention in therotary table.

The present invention may be embodied in bushings ier use in rotarytables of various makes and designs. in the following detaileddescription T. will describe typical preferred forms of the invention asemployed in a specic form of rotary table, it being understood that theinvention is not to be limited or restricted to this particular form orapplication of the invention but is to he taken as including anyfeatures or modifications that may fail within the scope of the claims.

The rotary tablevT illustrated in Fig. l is supported for rotation abouta vertical axis by bearings B carried by a base I0. Teeth II areprovided on the under side of the table T and a driven bevel gear l2meshes with the teeth II to drive the table T. A central verticalopening I3 is provided in the table 'I' to receive the master bushing.The upper portion of the opening I3 is square or polygonal in crosssection and has downwardly and inwardly tapered Walls while i the lowerportion of the opening I3 is cylindrical and has a vertical wall. Anupwardly facing shoulder I4 occurs on the wall of the opening I3 whereits polygonal and cylindrical portions join.

The improved master bushing of the present invention illustrated inFigs. l to '7, inclusive, may be said to comprise, generally, bushingsections A and B for arrangement in the table opening I3, wedge elementsI5 for acting between the sections A and B and means I6 for controllingand actuating the wedge elements I5.

The bushing sections A and B form an assembly that constitutes the bodyof the master bushing. In the construction illustrated there are twolike complementary sections A and B, that is, the bushing is divided ona vertical diametric plane. The sections A and B are shaped andproportioned to accurately fit the opening I3 in the table 'I' withsufficient clearance to allow the bushing to be inserted in the table.The two sections A and B have polygonal upper parts or heads Il foritting in the polygonal upper portion of the opening I3 so that themaster bushing rotates with the table T. The sides of the heads I'I aretapered to conform to the tapered walls of the upper portion of theopening I3. The lower sides of the heads I1 form downwardly facingshoulders I8 which rest on the shoulder I4 in the table T. The lowerportions I9 of the sections A and B have cylindrically curved eX-teriors to t or enter the cylindrical lower portion of the opening I3.The upper ends of the sections A and B are flat and are adapted to lieiiush with the upper surface of the table T. The inner opposing faces 20of the sections A and B occurring at the vertical plane of division ofthe bushing are flat and vertical.

In accordance with the invention the heads il and portions I8 of thesections A and B have blocks or inserts 8 of rubber, rubber composition,or the like, for cooperating with the walls of the opening I3 to absorbshock and slap and to take the wear. The inserts 9 may initiallyprotrude from the external surfaces of the sections A and B and arecompressed when the bushing is seated in the table opening i3. Theinserts 9 are set or vulcanized in spaced recesses 8 in the externalsurfaces of the bushing sections A and B. When the bushing is seated inthe table T the com pressed resilient inserts 9 effectively absorbshock, take the wear and assist in holding the bushing tight in thetable T.

The master bushing has a central vertical opening 2I, that is, thesections A and B are shaped to define or provide a vertical opening 2i.The opening 2| is provided to pass the drilling tools, to receive pipeengaging slips, to receive the drive bushing and to pass and receiveother well drilling equipment. The upper portion of the opening 2I ispolygonal or square and the walls of the opening taper downwardly andinwardly from this square portion. The sections A and B are hollow orcored out, each having a chamber 22 between its inner and outer walls.The chambers 22 are preferably open at the lower ends of the sections Aand B. Reinforcing webs 23 may be provided in or may extend through thechambers 22. The elements and parts of the two sections A and B thus fardescribed may be identical and I have applied corresponding ref erencenumerals to the corresponding parts of the sections A and B describedabove. A pair of spaced sockets or openings 24 is provided in the upperend of the section B to receive the fingers 25 of a. lifting tool 26 ofthe character illustrated in Fig. 7. Similar but somewhat largeropenings 2'I are provided in the upper end of the section A to receivethe ngers 25 of a lifting tool 26.

The wedge elements I5 when active operate to hold the bushing sections Aand B tight against the walls of the opening I3 and thus preventvibration of the master bushing in the table T. In the preferredconstruction there are two wedge elements I5 carried by the bushingsection A to cooperate with the section B. The elements I5 are arrangedat the inner faces 20 of the section A to coopera-te with the opposingfaces 20 of the section B and the section A is shaped to reoeive thewedge elements. A vertical recess 28 is provided in each face 20 of thesection A. The side walls of the recesses 28 are fiat and vertical whilethe inner walls of the recesses have pluralities of stepped downwardlyand outwardly inclined faces 29. The wedge elements I5 are arranged inthe recesses 28 and are shaped to cooperate with the faces 29. The wedgeelements I5 are elongate members having dat vertical sides adapted toride on the side walls of the recesses 28. The outer or rear sides ofthe Wedge elements I5 are provided with series of stepped downwardly andoutwardly inclined wedge faces 30. The wedge faces 30 shiftably orslidably cooperate with the faces 29. The active or inner surfaces 3I ofthe wedge elements I5 are fiat and vertical and are preferably machinedto better cooperate with the opposing faces 20 of the section B. Whenthe wedge elements I5 are in their retracted or up positions illustratedin Figs. 4, 5 and 6, their surfaces 3l are ush with or inset from thefaces 20 of the section A.

Means are provided for limiting the movement of the wedge elements I5and for retaining the elements on the section A. vertically spaced slots32 are provided in the wedge elements I5 and are inclined in parallelrelation with their wedge faces 30. Pins 33 are carried in horizontalopenings 34 in the section A and pass through the slots 32 to limit themovement of the elements I5. Plugs 35 may be threaded in the outer endsof the openings 34 to hold the pins 33 against dis placement. The pins33 cooperating with the slots 32 guide the wedge elements I5 formovement in a direction parallel to the faces 29 and limit the movementof the wedge elements so that the elements are at all times within theconfines of the upper and lower ends of the section A.'

The means I6 are provided to actuate the wedge elements I5 and hold themactive while the bushing is in the table T and are operable to retractthe elements I5 to permit the easy insertion and removal of the bushingsection A. There is a means IE provided for each wedge elcment I5 andthe two actuating means IG may be identical. The actuating andcontrolling means I6 are contained within the hollow or cored outbushing section A.

Each means I5 includes pivoted lever 36 supported by a pin 31. The leversupporting pins 3T are arranged in horizontal openings 38 in the head I1of the section A. Plugs 39 may be threaded in the outer ends of theopenings 38 to hold the pins 31 in place. Each lever 36 has an arm orfinger 4U received in a socket 4I in the back or rear side of theadjacent wedge element I5. The forward ends of the fingers 40 arerounded to move or work in their sockets 4I. Each lever 395 furtherincludes an outwardly or rearwardly projecting arm 42. The levers 36 arelocated so that their arms 42 are adjacent and directly below theadjacent openings 21 in the upper end of the section A. The lever arms42 have openings 43 in substantially vertical alignment with theadjacent openings 2T and the openings 43 are adapted to receive ythehooks or fingers 25 of the tool 26. The outer ends of `the lever arms 42have transverse bar-like parts 44 adapted to be engaged by the fingers25 of the tool 26 as illustrated in Figs. 4 and 5 of the drawings. Itwill be observed that the two fingers 25 of the tool 26 maysimultaneously cooperate with the lever arm parts 44 to simultaneouslypivot the two levers 36. When the lever arms 42 are pulled or movedupwardly by the tool 26 the inner arms or fingers 40 move downwardly andcooperation of the fingers with the sockets 4I produces downwardmovement and retraction of the wedge elements I5.

The means I6 further include springs 45 acting on the levers 36 toactuate the wedge elements I5 andto hold the wedge elements in theiractive positions. The springs 45 are preferably in the nature ofextensible helical springs and are arranged in the chamber 22 of thesection A. The upper ends of the springs 45 are hooked or looped in eyes46 on the outer ends of the lever arms 42. Suitable eyes 4'I areprovided on the lower wall portion of the chamber A and the lower endsof the springs 45 are engaged or hooked .in these eyes 41. The springs45 are normally under tension and normally exert downward forces on thelever arms 42. Thus the springs 45 exert an upward force on the wedgeelements I5 through the medium of the pivoted levers 35 acting as cams.It is to be observed that the actuating forces exerted by the springs 45.transmitted by the cani-like levers 36 are continuous and constant sothat the wedge elements are at all times urged outwardly throughcooperation of the inclined faces 2S and 30. The spring urged wedgeelements I5 forced outwardly against the opposing faces 20 of thesection B act to force the sections A and B apart and maintain the outerSurfaces of the sections in tight cooperation with the walls of therotary table opening I3.

In the use or operation'of the assembly shown in Figs. 1 to 7 inclusive,thesections A and B may be lowered into the rotary table T by means oflifting tools 26 of the character shown in Fig. 7. It is preferred toeither lower the two sections A and B in the opening I3 simultaneouslyor to first arrange the section B in the table and then lower thesection A into place. When the section A is held or suspended by meansof a tool 26 the tool holds the levers 36 in a position where the wedgeelements I5 are fully retracted. This is clearly illustrated in Figs. 4and 5 of the drawings. Accordingly, when the section A is lowered intothe rotary table opening I3 simultaneously with the section B orfollowing the section B the wedge elements I5 are retracted and do notcontact the section B or interfere with the insertion of the section A.

When the section A is in place in the opening I3 and the tool 26 isdisengaged from the section the springs 45 pivot the lever arms 42downwardly and thus move the wedge elements I 5 upwardly. This upwardmovement of the wedge elements I5 is accompanied by sliding cooperationof the faces 29 and 30 which causes inward movement of the elements I5against the opposing faces 20 of the Section B. The springs 45 actingthrough the medium of the levers urge the wedge elements I5 against thefaces 20 of the section B with sufficient force to hold the externalsurfaces of the two sections A and B in tight engagement with the wall-Sof the rotary table opening I3. The engagement of the surfaces 3| of thespring-urged wedge elements I5 with the opposing faces 20 of the sectionB prevents relative movement and working of the two bushing sections Aand B. In practice the spring urged wedge elements I 5 carried by thesection A and acting against the section B fully take up the necessarytolerance or clearance between the sections A and B and between thesections and the walls of the opening I3 and serve to prevent vibrationof the master bushing in the rotary table T. The springs l45 exertingcontinuous and substantially constant forces on the wedge elements I5assure the proper functioning of the wedge elements throughout the timethat the master bushing remains in the rotary table T.

When it is desired to remove the master bushing from the table T it ispreferable to remove the section A before removing the section B. A tool26 is manipulated so that its fingers 25 engage the lever parts 44 andthe tool iS then raised to lift the section AA from the rotary table T.The upward force exerted on the tool 26 causes upward pivoting of thelever arms 42 and downward swinging of the lever fingers 4I). This, ofcourse, results in downward shifting of the wedge elements I5 andretraction of the wedge elements. Thus the wedge elements I5 areautomatically retracted when the section A is withdrawn from the rotarytable T.

In the form of the invention illustrated in Fig. 8 the means I6a forholding the bushing.

sections tight inthe opening I3 of the table T are in the nature ofsimple cam means. The section B of the structure shown in Fig. 8 may beidentical with the section B described above and the section A may besimilar to the section A except that it is devoid of the recesses 28 andthe wedge faces 29. Openings 50 are provided in the faces 2lia of thesection A to communicate with the interior of the hollow section.

The means I6u include cam levers 36ab pivotally supported within thesection A. The levers 36a are supported on horizontal pins 31a and havetheir rear arms 42a below the openings 21e in the top of the bushingsection A. The lever arms 42EL have openings 43a to receive the fingers25 of the tool 26 and have parts 44ab engageable by the said ngers forthe purpose of releasing or retracting the means |621. Springs 45asubstantially identical with the above described springs 45 areconnected with eyes 46*l on the ends of the lever arms 42e. The springs45a actuate or urge the lever arms 42a downwardly. The forward cr activearms 4IIi of the levers 36HL are in the nature of cams having curved camfaces 5I cn their outer ends. The cam faces 5I are formed and shaped tocam or bear against the surfaces 2D of the section B to urge thesections A and B apart and thus maintain the sections tight in the tableopening I3.

The form of the invention illustrated in Fig. 8 operates insubstantially the same manner as the previously described form of theinvention. When the bushing is seated in the opening I3 of the table Tthe springs 45a acting on the levers 36a maintain the cam faces 5I incamming or pressure engagement with the faces 20 0f the section B. Thisengagement in turn maintains the sections A' and B tight in the tableopening I3 and resists or prevents slap and movement of the bushing inthe table opening. The cam levers 36eare adapted to be retracted by thetool 26 in the same manner as the levers 36. The structure illustratedin Fig. 8 is characterized by its simplicity.

Having described only typical preferred forms and applications of myinvention, I do not wish to be limited or restricted to the specicdetails herein set forth, but wish to reserve to myself any variationsor modications that may appear to those skilled in the art or fallwithin the scope of the following claims.

Having described my invention, I claim:

1. A bushing for arrangement in the opening of a rotary table comprisingbushing sections to be inserted in the opening, and a spring urgedelement engaging between the sections to urge the sections apart andhold them against the walls of said opening.

2. A bushing for arrangement in the opening of a rotary table comprisingbushing sections to be inserted in the opening, acam on one sectionengaging the other section to prevent movement of the bushing sectionsin the opening, and spring means urging the cam against said othersection.

3. A bushing for arrangement in the opening of a rotary table comprisingbushing sections to be inserted in the opening, and means for preventingvibration of the bushing sections in the opening, said means including avertically shiftable wedge element carried by one section and engagingthe other section, and means for actuating the wedge element.

4. A bushing for arrangement in the opening of a rotary table comprisingbushing sections to be inserted in the opening, and means for preventingmovement of the bushing sections in the opening, said means including anelement shiftably carried by one section to cooperate with anothersection, and spring means actuating the said element.

5. A bushing for use in the opening of a rotary table comprising atleast two bushing sections for arrangement in said opening, and meansfor preventing play of the sections in the opening comprising a wedgeface on one section, a wedge element shiftable on said face and adaptedto bear against the other section, and spring means acting on .the wedgeelement to urge it along said face.

6. A bushing for use in the opening of a rotary table comprising atleast two bushing sections for arrangement in said opening, and meansfor preventing play of the sections in the opening comprising a wedgeface on one section, a wedge element shiftable on said face and adaptedto bear against the other section, a pivoted lever on the firstmentioned section operatively connected with the wedge element, and aspring acting on the lever to move the wedge element along said face.

7. A bushing for use in the opening of a rotary table comprising atleast two bushing sections for arrangement in said opening, and meansfor preventing play of the sections in the opening comprising a wedgeface on one section, a wedge element shiftable on said face and adaptedto bear against the other section, a pivoted lever on the iirstmentioned section for operating the wedge element, and a spring normallyacting on the lever to cause the wedge element to wedge against saidother section, said first mentioned section having an opening renderingthe lever accessible for the purpose of retracting the wedge element.

8. A bushing for the opening of a rotary table comprising two bushingsections arranged in the opening, there being a vertical opening throughthe sections, inclined faces on one section at opposite sides of thelast named opening, wedge elements shiftable on said faces to be forcedagainst the other section to hold the sections tight in the rstmentioned opening, and means on the rst named section for actuating thewedge elements.

9` A bushing for the opening of a rotary table comprising two bushingsections arranged in the opening, there being a vertical opening throughthe sections, inclined faces on one section at opposite sides of thelast named opening, wedge elements shiftable on said faces to be forcedagainst the other section to hold the sections tight in the firstmentioned opening, means for actuating the wedge elements, and means fmsimultaneously retracting the elements.

10. A bushing for the opening of a rotary table comprising two bushingsections arranged in the opening, there being a vertical opening throughthe sections, inclined faces on one section at opposite sides of thelast named opening, wedge elements shiftable on said faces to be forcedagainst the other section to hold the sections tight in the rstmentioned opening, levers pivoted on the rst named section for shiftingthe wedge elements, springs acting on the levers to urge the Wedgeelements against said other section, and means for simultaneouslyretracting the wedge elements.

LAWRENCE F. BAASH.

